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NAE5510

I have a site that we recently turned over. its really been solid commuication although there are a ton of controllers(350) and no ADS. Anyways my question is there was a power outage Sunday(1.5 hours). I got a call that a few VMA's were offline. I logged in remotely and all devices were online. When I opened up a device all the points showed up as offline. the controllers did not have blue or red x's. The point reliability said communication failure. When I pulled up the Device in CCT everthing was normal. I even opened up the FC bus and went to engineering. Discovered all devices and points. Same issue. Any ideas?

I've ran into a similar situation. The building i was working on had got struck by lightning. The the NAE was showing the controllers online but the points had all gone unreliable. It turns out there were 3 UNTs that had got smoked and were bring the bus down. I would start going around the building and unplugging the FC Bus. Either that or do divide and conquer which might be easier since you have 350 devices.

Every time that the whole bus goe offline (network unit+field devices) there is a period at which network unit must recover its online state, field devices then obtain online state, and finally control points of each device come online...

The definition period of entire system coming online depends of total amount of field devices on trunk..
If i can recal correct there is a 5min-15 min period for each device on trunk (for NCM units), there was a project that I had to wait for 3 hours!!! for everything to come normal again...

After a safe period start looking around for smoked field controllers, that are not comunicating at all (always offline), or controllers that interfere on bus communication and do not allow recovery (creating cycled offlines on other bus devices...), I have seen also that...

I've seen it on a start-up before as the NAE is booting up and hasn't yet finished polling all the devices yet. Because you have 350 (?!) devices it will probably take the NAE a while to finish all its start-up tasks. BTW what kind of CPU usage and memory usage are you seeing? That goes way above and beyond JCI's published recommedations for an NAE. How many trunks? MSTP, LON, or N2 devices? Point count? Just curious, I didn't think an NAE could handle that many.